1. Technical Field
One or more embodiments of the present invention relate to cathode active material compositions, cathodes prepared from the compositions, and lithium batteries including the cathodes.
2. Description of Related Art
Recently, the demand for mobile phones and their technological development has increased, thus increasing the demand for secondary batteries as energy sources. Among these secondary batteries, lithium secondary batteries having high energy density and high voltage have become commercialized and are widely used.
A lithium secondary battery generally uses a lithium complex oxide as the cathode active material. The cathode active material is a lithium compound capable of intercalating or deintercalating lithium ions.
When an electrode plate is prepared using a water-based binder containing the cathode active material and a thickener, the electrode is strongly basic because unreacted alkali metal ions or alkali metal ions dissociated in the water present with the cathode active material increases the pH.
When a strongly basic water-based cathode active material slurry is coated on an aluminum electrode base material, the aluminum electrode base material corrodes due to the high pH, generating H2 gas, generating a large number of pin holes in the electrode base material, and increasing the internal resistance of the electrode base material.
Therefore, a demand exists for cathodes that prevent increases in internal resistance by preventing corrosion of the electrode base material, and a demand exists for lithium batteries having improved high-rate characteristics and lifespan characteristics.